The invention relates to a cutter having indexable cutting inserts for metal cutting operations.
Cutting inserts are mounted and held in cutting tools by a variety of methods, such as by screws, clamps, pins, and the like. Traditionally, screw-on cutting inserts are securely held to the tool holder body with an insert screw that passes through a hole formed in the insert and threads into the tool holder body. There have been times where the head of the insert screw would adversely affect chip flow due to its protrusion into the chip forming area of the cutter. Chips can deposit or pack in the screw socket and around the head of the screw, depending on the workpiece material and cutting conditions, making the screw difficult to remove. Also, if the insert screw was too long, the insert screw may protrude out the back of the cutter and rub on the workpiece during cutting operations. On small diameter cutters, the lack of thread engagement is also a concern.
Therefore, there is a need to provide a cutting insert that allows better chip flow by eliminating the possibility of the head of the mounting screw becoming a barrier to chip flow, and the need to tap the screw hold, thereby simplifying the manufacturing process and significantly reducing cycle times in the cutter.